Robin Williams’ death has confronted Hollywood once more with the troubles haunting some of its stars, despite the movie industry’s efforts to improve mental health support for its employees.

The list of stars who took own lives or succumbed to addiction is long, and includes Philip Seymour Hoffman, Heath Ledger, Brittany Murphy, River Phoenix, Judy Garland and Marilyn Monroe.

Others have survived but struggle with alcohol, drugs or depression, like tabloid staple Lindsay Lohan.

Lena Dunham, the young comic star and creator of the Girls series, took to Twitter to eulogise Williams, one of the most accomplished and recognised actors of his generation.

But she also stressed that his death served as a “tragic reminder that the conversation about mental health CANNOT stop. Money, fame, artistic freedom – none of it is a barrier.”

Some critics question whether the demanding television and movie industry does enough to protect its stars from their personal demons.

But Bull’s Eye Entertainment production company owner Tom Nunan said the industry was not to blame for personal tragedies.

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“The bigger issue is US and Western culture not making clear enough that there are ways out,” said Nunan, who teaches at the UCLA School of Theater, Film and Television.

He said proper treatment could help sufferers and called for more vigilance about depression and addiction in the United States, where about 100 people commit suicide each day.

The Screen Actors Guild contract provides health insurance that covers addiction treatment.

And the non-profit Motion Picture and Television Fund provides health insurance to industry members who can’t afford it.

The group is among several programs that pay for psychotherapy, including MusiCares MAP Fund for the music industry.

Psychotherapist Judi Bloom noted that artists who had been treated for alcoholism, addiction, depression and other ailments were readily hired and rarely ostracised.

“The industry is incredibly accepting in embracing people and letting them know it’s a disease and not a problem with their character or their weakness,” said Bull’s Eye’s Nunan.

And “Los Angeles is much more tolerant than most American cities,” said psychologist Tricia Doud.

“There is no stigma here when you say you have a therapist.”

For Bloom, the fact that the addiction and depression problems of stars attract more attention than for the average person is a “good thing” because it shines a light on the issue.

But “the problem of addiction is a far larger problem” that affects society as a whole, she stressed.

Artists are generally highly narcissistic, but that does not mean that every artist is an addict, Bloom says.

“Creative impulse means constantly seeking some kind of validation,” which can trigger a sense of emptiness and a quest for validation from others, she added.

Williams had struggled openly with his addictions and depression for years, and had received help, including from the highly reputed Hazelden Addiction Treatment Center.

“Medical science is not perfect,” Bloom said.

“Say you have somebody with a heart condition. You give them all the medication you know. You advise them on diet, on all the aspects of your life. They’ll still die of a heart attack.

“It is the same with depression.”